The present invention relates to power saving apparatus for use with battery-operated devices and, more particularly, power saving apparatus that can be inserted between series connected batteries within the battery-operated device to disable the power supply.
There are many battery-operated devices that use two or more series-connected batteries. However, many of these battery-operated devices do not have any mechanism for conserving power other than the user turning the device on or off. For example, two xe2x80x9cDxe2x80x9d size batteries are often used in series in a standard flashlight. Once the flashlight is turned on, the flashlight continues to consume power from the batteries until the user turns off the flashlight. One problem is that the user may forget to turn off the flashlight when finished, or the flashlight may be accidentally turned on when stored in a toolbox, drawer, etc. Of course, many other battery-operated devices (e.g., toys, radios, etc.) are susceptible to this problem.
One solution to this problem is to provide a xe2x80x9csmartxe2x80x9d device that can monitor the status of the batteries. For example, many devices have a xe2x80x9csleepxe2x80x9d mode that turns off the device or reduces the power consumption of the device after a predetermined period of time during which the device was not used or had no activity. However, this solution does not address the problem of existing devices that do not have this capability. Accordingly, there is a need for a power saving apparatus that can be easily and inexpensively retrofitted to existing battery-operated devices.
In accordance with aspects of the present invention, a power supply disabler that can be retrofitted to a battery-operated device is provided. In one aspect of the invention, the power supply disabler includes a resettable timer, a switch and a pair of electrodes, all of which are fitted in a thin profile case. The case is configured to fit between a pair of series-connected batteries while the batteries are installed in the battery-operated device. In operation, the power saving apparatus is inserted between a pair of batteries of the battery-operated device. Initially, the timer is turned off and the switch is closed so that the power saving device provides a conductive path between the batteries. When the battery-operated device is turned on, the timer is reset and initiated while the switch maintains the conductive path. After a predetermined time period, the timer causes the switch to open-circuit the conductive path, thereby disabling the power supply. Thus, the power supply is prevented from supplying power to the battery-operated device. In one embodiment, the predetermined time period is about twenty minutes. The timer is reset when the battery-operated device is subsequently turned on for the next use.